How do I change the FPS of a recorded video?

I recorded multiple videos with the Camera app of the Galaxy S5 with the Recording mode set to "Fast motion" at x4 speed. It was a misunderstanding, but I actually wanted to record the videos in slow motion at x1/4 speed.

The videos have already been recorded, so is there a way to convert these recorded videos I have into 120 fps (slow motion at x1/4 speed)? Either by some setting from the phone, the Play Store, or a program on the computer?

In short, how do I make a recorded video that I recorded into a video recorded at a different fps/slow?

I recorded multiple videos with the Camera app of the Galaxy S5 with the Recording mode set to "Fast motion" at x4 speed. It was a misunderstanding, but I actually wanted to record the videos in slow motion at x1/4 speed.

The videos have already been recorded, so is there a way to convert these recorded videos I have into 120 fps (slow motion at x1/4 speed)? Either by some setting from the phone, the Play Store, or a program on the computer?

In short, how do I make a recorded video that I recorded into a video recorded at a different fps/slow?

Thank you very much!

I would try kinemaster app. It's free but has watermark. It's damn nice interface. I found promo code that gave free month no watermark today. I would do that to change speed of vid. Here code ITGQIUUKD8U2L72N

I recorded multiple videos with the Camera app of the Galaxy S5 with the Recording mode set to "Fast motion" at x4 speed. It was a misunderstanding, but I actually wanted to record the videos in slow motion at x1/4 speed.

The videos have already been recorded, so is there a way to convert these recorded videos I have into 120 fps (slow motion at x1/4 speed)? Either by some setting from the phone, the Play Store, or a program on the computer?

In short, how do I make a recorded video that I recorded into a video recorded at a different fps/slow?

Thank you very much!

This video shows you the fastest way (literally takes like 2 minutes):